diff --git a/Barotrauma/BarotraumaClient/Source/GameSession/GameModes/Tutorials/DoctorTutorial.cs b/Barotrauma/BarotraumaClient/Source/GameSession/GameModes/Tutorials/DoctorTutorial.cs
index 0c5bef294..95b87e82e 100644
--- a/Barotrauma/BarotraumaClient/Source/GameSession/GameModes/Tutorials/DoctorTutorial.cs
+++ b/Barotrauma/BarotraumaClient/Source/GameSession/GameModes/Tutorials/DoctorTutorial.cs
@@ -21,7 +21,7 @@ namespace Barotrauma.Tutorials
         private ItemContainer doctor_suppliesCabinet;
         private ItemContainer doctor_medBayCabinet;
         private Character patient1, patient2;
-        private List<Character> subPatients = new List<Character>();
+        private List<Character> subPatients;
         private Hull startRoom;
         private Hull medBay;
 
@@ -47,6 +47,7 @@ namespace Barotrauma.Tutorials
         {
             base.Start();
 
+            subPatients = new List<Character>();
             radioSpeakerName = TextManager.Get("Tutorial.Radio.Speaker");
             doctor = Character.Controlled;
 
diff --git a/Barotrauma/BarotraumaClient/Source/Screens/ServerListScreen.cs b/Barotrauma/BarotraumaClient/Source/Screens/ServerListScreen.cs
index 0344ba7c1..1f146ab06 100644
--- a/Barotrauma/BarotraumaClient/Source/Screens/ServerListScreen.cs
+++ b/Barotrauma/BarotraumaClient/Source/Screens/ServerListScreen.cs
@@ -218,6 +218,22 @@ namespace Barotrauma
             return true;
         }
 
+        private bool RefreshJoinButtonState(GUIComponent component, object obj)
+        {
+            if (obj == null || waitingForRefresh) { return false; }
+
+            if (!string.IsNullOrWhiteSpace(clientNameBox.Text) && !string.IsNullOrWhiteSpace(ipBox.Text))
+            {
+                joinButton.Enabled = true;
+            }
+            else
+            {
+                joinButton.Enabled = false;
+            }
+
+            return true;
+        }
+
         private bool SelectServer(GUIComponent component, object obj)
         {
             if (obj == null || waitingForRefresh) { return false; }